Bulging and herniated discs are another of those phrases commonly used but seldom totally understood. The mental image of a disc slipping in and out of place may add to the confusion. For a better understanding of disc problems and how they affect the back, a quick lesson in anatomy is required.
The discs, often referred to as intervertebral discs, lie between the vertebrae making up the spine. They act as spacers and shock absorbers and resemble a jelly donut in that they have an outer layer, called the annulus, and a jelly-like inner filling called the nucleus pulpulsa. At every vertebrae of the spine, nerves exit in pairs, one to the left, one to the right. These include 7 cervical (neck) vertebrae, 12 thoracic (mid-back) vertebrae, and 5 lumbar (low back) vertebrae. If the outer layer of the disc starts to thin, the jelly-like inner layer can cause a bulge. Pain usually occurs when this bulge presses against one of the exiting nerves at that level.
Biomechanically, discs tend to bulge more at the neck and low back. They seldom are found in the mid-back. In studies on the pressure in intervertebral discs, sitting and bending forward put a person at the greatest risk. Another study found that a large number of people are walking around totally unaware of their bulging discs. A bulge doesn’t necessarily mean that a person has pain, since it may not put pressure on a nerve. The disc bulge usually has to be fairly large and protrude to the back and somewhat to the side to create compression of the nerve, due to its location.
A herniated/ruptured disc or HNP (herniated nucleus pulposus) is a situation in which the jelly portion has squished out of the donut in our original example. This is a more serious problem, especially if the fragments of jelly (nucleus pulposus) compress the nerve.
Symptoms of nerve compression from discs can include pain, numbness and tingling (parathesia), muscle weakness, and loss of reflexes, usually corresponding to a specific nerve level that is being compressed. In the case of a cervical disc, it usually means symptoms are present in one arm, and in the case of a lumbar disc, symptoms are present in one leg. It is actually not uncommon to have little or no pain in the spine and experience most of the symptoms in the extremity.
In combination with clinical findings, non-invasive tests such as an MRI usually indicate not only the presence of a bulge or herniation, but also give some information on the amount of compression. An orthopedic surgeon, a neurologist or a neurosurgeon usually assists in making a disc diagnosis.
Treatments for disc problems vary greatly. From a manual physical therapist’s standpoint, disc problems occur because either too much stress is placed on structures that aren’t in correct biomechanical alignment, or because of repetitive bending and lifting of objects far too heavy. Often, the back pain a person experiences along with a disc problem emanates from the biomechanical cause. This can include anything causing your pelvis to be asymmetrical or your posture to be crooked or slouched. Frequently, when these biomechanical issues are corrected, the overall pain significantly diminishes. An exercise program focusing on back and abdominal strengthening along with stretching can be done after the biomechanical issues are resolved.
In severe injuries or in the case of herniated discs, disc fragments may require surgical removal. When all other contributing factors have been dealt with, this surgical procedure often provides immediate and substantial relief to the nerve pain.
Rehabilitation following surgery is usually advised, depending on the length of incapacitation prior to surgery and the demands of the individual’s lifestyle.
Lastly, prevention is the preferred way to deal with these problems. Proper ergonomic set up when sitting at work or in the car is very important, especially in providing a good support for the lumbar curve of your low back. Maintain good postural alignment through exercise and don’t abuse your back by bending to lift objects that are too heavy.
Remember, only you can prevent back problems!